Abstract: According to the process the sludge is homogenized and heated to 30.degree.-60.degree. C. temperature. The heated sludge is circulated under 2-4 bar overpressure, and its temperature is raised to about 130.degree.-150.degree. C. in 1-2 sec by conducting steam of 130.degree.-151.degree. C. and 2-4 bar pressure directly into the sludge, thus granulation is brought about in the sludge. The sludge of increased temperature--while its temperature and pressure maintained--is further circulated for about 60-300 sec. Then, the sludge is adiabatically expanded in 1-2 sec by reducing the pressure to about 0.01-0.02 bar. The expanded sludge is separated to water, fat containing water and solid impurity and wet solid phase containing protein.It is characteristic to the apparatus that it is provided with device for heating the sludge, and pipe (18) for passing on the heated sludge connected with the heating unit (5) where an expansion valve is built in.

Abstract: In a method of and apparatus for recovering mercury from drainage, mercury-containing waste water is fed into a first treating tank where the waste water is heated together with a metal having a stronger ionizing tendency than mercury, to reduce mercury ions in the waste water and free the mercury ions as metallic mercury. The solution under treatment is then transferred to a second treating tank where the solution is alkalinized, and mercury ions remaining in the solution is reduced by means of a water soluble metallic salt having a stronger ionizing tendency than mercury, to free the mercury ions as metallic mercury. Mercury vapor containing gases generating from the first and second treating tanks are cooled in a cooling device, and condensed and liquefied mercury is collected in a gas-liquid separator. Exhaust gas generating from the gas-liquid separator is fed into the solution under treatment in the second treating tank.

Abstract: Phosphoric acid wastewater treatment to substantially eliminate discharge of contaminants to the environment. Acid pond water from conventional wet-phosphoric acid manufacturing is replaced by gypsum pond water having a pH closely matching that of the surroundings. Essentially all fluorides are insolubilized and substantially all phosphoric acid is recovered, minimizing loss to the environment.

Abstract: In the processing of a geothermal brine and the recovery of heat therefrom, there are produced a non-condensable gas stream containing hydrogen sulfide and carbon dioxide and a liquid stream comprising a condensate of steam derived from the brine. In accordance with the present invention, the noncondensable gases are introduced into the condensate in the presence of an oxidizing agent to form a gas-liquid mixture. The mixture is maintained at an alkaline pH for a time sufficient for a substantial portion of the hydrogen sulfide to be oxidized. Thereafter, the mixture is introduced into a gas-liquid separation zone for separate recovery of a gas stream comprising a major amount of carbon dioxide and substantially free of hydrogen sulfide. Advantageously, the recovered gas stream is recycled to the geothermal brine process to reduce the pH of the brine and its scaling potential.

Abstract: An apparatus and a process for using the apparatus for removing fat, bacteria, solids and other impurities from water used in food processing so that substantially all the water may be reused includes a tower. The water is passed through a coarse filter to remove large pieces and is then introduced into the tower near the top thereof and flows out the tower near the bottom thereof. A mixture of ozone and air is introduced at the bottom of the tower and bubbled up through the tower, counter to the flow of the water. The ozone and water mixture carries impurities, especially the fat, over the top of the tower as a foam. The foam then flows over the tower into a waste drain. The process and apparatus may be varied to include a second tower unit with an alternative intermediate filter unit between the first tower and second tower unit.

Abstract: Methods are provided for removing contaminants from an aqueous solution to yield a less contaminated aqueous effluent. In one embodiment of the invention, the method comprises coprecipitating non-volatile contaminants (i.e., heavy metals, light metals, cyanide, phenolics, oil and grease, TSS, BOD, COD, and/or TOC) with a carrier precipitate which is formed in situ within the aqueous solution. In another embodiment of the invention, the method comprises partitioning volatile organic contaminants between a liquid phase and a gas phase. In yet a further embodiment, the above versions of the invention are simultaneously performed in the same reaction vessel.

Abstract: This invention relates to the removal of hypochlorite groups from aqueous effluent solutions, so as to permit the disposal of the effluent by deep well injection. More particularly this invention relates to the catalytic decomposition of such hypochlorite groups from scrubbing water effluent used to remove chlorine from a gaseous effluent, wherein a solid catalyst is dissolved, recycled and reprecipitated in situ.

Abstract: A process for separating emulsified, suspended and separate oil as well as other contaminants from the water phase of a compressed air system condensate comprises the steps of discharging air and condensate from a compressed air system into a water filled separation tank where air is separated from the condensate. Some of the contaminants heavier than water are allowed to settle to the bottom of the separation tank while lighter oil contaminants are allowed to float to the surface where they are removed. Water and the remaining contaminants which did not flow to the surface or settle to the bottom of the tank are drained away until a given amount of liquid mass has been accumulated. Pressure applied to the liquid mass forces the mass into and through an underwater coalescing media. Such action causes substantially all of the remaining oil constituents to coalesce and thereby form a floating oil phase while other contaminants are retained by the coalescing media.

Abstract: The invention provides a chemical process for the treatment of water containing dissolved calcium and sulphate ions, so as to produce a purified product water having a reduced sulphate ion concentration. Barium sulphide is added to the water to cause precipitation of barium sulphate from the water. The water from which the barium sulphate has been precipitated is then treated with carbon dioxide to form hydrogen sulphide in the water, and the hydrogen sulphide is stripped from the water.

Abstract: A method of removing dissolved and colloidal macro-molecular organic substances from effluents from processes used in the manufacture of pulp and paper, wherein an acid sludge containing cellulose fibres and being acidified to a pH value of 1.6-2.5, is added to an effluent containing said organic substances, and the pH value is adjusted to 4.5-6.0 before the mixture is subjected to sedimentation to achieve precipitation of the fibres with said organic substances adhered thereto. According to the invention the fibres used as precipitant are subjected to mechanical treatment prior to said acidification, so that the fibres are broken and split open, increasing their specific fibre surface and thereby their ability to catch the organic substances in the effluent.

Abstract: The present invention relates to a high rate method for combining waste materials to produce valuable products for agricultural, horticultural, sylvicultural or public use. Specifically, the present invention combines the steps of alkaline stabilization, beneficiating and pelletizing waste materials, such as wastewater treatment plant sludge or animal excrement and reaction with carbon dioxide, to thereby convert the waste materials to useful products such as soil conditioners or fertilizer supplements.

Abstract: Methods and apparatus for controlling the movement of materials having different physical properties when one of the materials is a fluid. The invention does not rely on flocculation, sedimentation, centrifugation, the buoyancy of the materials, or any other gravity dependent characteristic, in order to achieve its desired results. The methods of the present invention provide that a first acoustic wave is propagated through a vessel containing the materials. A second acoustic wave, at a frequency different than the first acoustic wave, is also propagated through the vessel so that the two acoustic waves are superimposed upon each other. The superimposition of the two waves creates a beat frequency wave. The beat frequency wave comprises pressure gradients dividing regions of maximum and minimum pressure. The pressure gradients and the regions of maximum and minimum pressure move through space and time at a group velocity.

Abstract: Separation of hydrocarbon vapors from an admixture of hydrocarbon gases and hydrocarbon liquid is achieved by passing the admixture into the upper portion of a vapor rfecovery zone comprising a vertical, elongated separation zone, withdrawing hydrocarbon gases from an upper portion of the separation zone, the admixture being introduced into the vapor separation zone below the point at which the hydrocarbon gases are withdrawn from said separation zone.The liquid introduced into the separation zone flows in a generally downward, vertical direction to a point in the lower portion of the vapor recovery zone, changing direction and flowing in an upward, substantially vertical direction forming a column of liquid. The is passed from the vertical liquid column to an oil retaining zone having an upper, gaseous zone and a lower liquid zone. The vertical liquid column maintains a seal between the gaseous zone of the oil retaining zone and the gas-containing upper portion of the separation zone.

Abstract: A process for abating hydrogen sulfide during geothermal steam stacking operations is disclosed. The geothermal steam to be stacked is introduced into a geothermal steam stacking line. Ferric chelating solution is injected into the stacking line in an amount effective to convert the hydrogen sulfide in the steam to sulfur. The hydrogen sulfide-abated steam and chelating solution is vented through a rock muffler and the chelating solution is optionally recovered from the muffler, regenerated and recirculated to the injection step.

Abstract: A method for waste treating metal containing solutions comprising decomposing the metal from the solution in the substantial absence of air and separating the decomposed (precipitated) metal from the solution.

Abstract: Hydrogen sulfide is removed from a water-in-oil emulsion by treatment of the emulsion with sulfur dioxide to convert the hydrogen sulfide to elemental sulfur. The elemental sulfur formed is distributed between the oil phase and the aqueous phase of the emulsion.

Abstract: Disclosed is a method for treating a photographic processing waste solution comprising concentrating the photographic processing waste solution containing at least thiosulfate ions, characterized in that there is provided at least one part selected from (i) to (v) shown below:(i) a part for adding sulfite ions or a compound capable of releasing sulfite ions into the photographic processing waste solution at the time or before heating of the photographic processing waste solution;(ii) a part for contact evaporated gas with a catalyst having a metal of the following (a) to (d) or a compound thereof carried thereon:(a) at least one selected from the group VIII elements consisting of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum,(b) copper,(c) zinc,(d) manganese;(iii) a part for permitting a water-soluble polymer to exist;(iv) a part for permitting an oxidizing agent capable of oxidizing thiosulfate ions to exist; and(v) a part for adding a pH controlling agent into the photogr

Abstract: A process for removing metals from water including the steps of prefiltering solids from the water, adjusting the pH to between about 2 and 3, reducing the amount of dissolved oxygen in the water, increasing the pH to between about 6 and 8, adding water-soluble sulfide to precipitate insoluble sulfide- and hydroxide-forming metals, adding a flocculating agent, separating precipitate-containing floc, and postfiltering the resultant solution. The postfiltered solution may optionally be eluted through an ion exchange resin to remove residual metal ions.

Abstract: Sour water is treated to remove dissolved hydrogen sulfide by means of an aqueous chelated polyvalent metal solution in a continuous recirculating system, particularly an autocirculation system, having reaction and oxygenation zones. The solution contains a small catalytic amount of chelated polyvalent metal, and the dissolved hydrogen sulfide is catalytically oxidized to sulfur in the liquid phase by means of dissolved oxygen in the solution. The sour water feed to the reaction zone is diluted by a massive recycle of oxygenated solution from the oxygenation zone before the sour water is contacted with air or other oxidizing gas used for oxygenating the used solution. A portion of the oxygenated solution containing chelated polyvalent metal is removed as the sweet water product, and replacement chelated polyvalent metal is added.

Abstract: A process and apparatus is disclosed for degassing liquids, particularly raw juices from fruits and berries. The liquid which is to be clarified or liquid residues remaining after clarification are subjected to degassing while circulating in a processing installation. A vacuum producing device is provided through which the liquids are circulated.

Abstract: A process is provided for simultaneously clarifying brine in a geothermal facility and producing silica seed material for use within the facility. A clarifier having an agglomeration zone therein is utilized and unclarified geothermal brine comprising silica solids is introduced into the agglomeration zone and thereafter circulated and mixed with the brine being clarified within the agglomeration zone to cause agglomeration of the particles therein. A circulation rate is maintained within the agglomeration zone to enable agglomerated solids therein to settle toward a lower portion of the agglomeration zone to form a sludge blanket, consisting essentially of silica and compounds of naturally occurring elements in the unclarified brine, while enabling clarified brine, having less solids than the unclarified brine, to pass out of the agglomeration zone for collection thereof.

Abstract: Methods and apparatus for controlling the movement of materials having different physical properties when one of the materials is a fluid. The invention does not rely on flocculation, sedimentation, centrifugation, the buoyancy of the materials, or any other gravity dependent characteristic, in order to achieve its desired results. The methods of the present invention provide that a first acoustic wave is progpagated through a vessel containing the materials. A second acoustic wave, at a frequency different than the first acoustic wave, is also propagated through the vessel so that the two acoustic waves are superimposed upon each other. The superimposition of the two waves creates a beat frequency wave. The beat frequency wave comprises pressure gradients dividing regions of maximum and minimum pressure. The pressure gradients and the regions of maximum and minimum pressure move through space and time at a group velocity.

Abstract: A method of removal of cyanide and metal ions from electroplating waste waters is described. The cyanide, as hydrogen cyanide, is purged with air and then absorbed efficiently in 1.5% sodium hydroxide solution. The purge is effected by dispersing air bubbles in the waste water after adjusting the pH of the water to one within the range of from 4 to 6.5. The cyanide ions are converted to hydrogen cyanide and entrained in the air bubbles for transport to a separate vessel for absorbtion in the sodium hydroxide solution. The apparatus employed is a closed system to avoid the hazards associated with hydrogen cyanide.

Abstract: A process for removing dissolved and undissolved oil and chemical additives from waste and/or produced water streams involves contacting a first gas with the produced water stream, the first gas utilizing hydrogen bonding and dipole interactions with the contaminants to remove them from the water. The rise rate of the first gas is accelerated by mixing a second, more buoyant gas with the first gas. The first gas and second gas are recovered by the application of a vacuum to the waste stream after treatment. The first gas is separated from the second gas by compressing and cooling the combined gas stream, venting the majority of the second gas stream while the first gas is liquified, then expanding the first gas before returning it to the flotation vessel. The first and second gases are mixed with the contaminated water stream at line pressure so that mixing is intimate and flotation is accelerated.

Abstract: A process and an apparatus are specified by which emulsions or suspensions of both different and changing composition can be separated in a particularly reliable manner. Proceeding on the principle of turbo-flotation, which is known per se, according to one embodiment, the gas is dispersed in the lower region of the vessel so that it is finely dispersed directly at the point where the emulsion is broken up or the suspension is separated, respectively, mechanically. Furthermore, the emulsion or suspension to be separated is supplied to the vessel close to the surface of the emulsion and the residue is removed at the bottom of the vessel. In this way, in continuous operation, a counter-flow between gas or gas/liquid suspension and emulsion can be achieved, thereby avoiding recontamination and re-emulsification. A strictly separated turbulence zone and a superposed flotation zone are formed. Foam carrying the flotate is formed on the surface.

Abstract: A system (10) is provided for treating wastewater discharged from airplane manufacturing operations. The system (10) includes a variety of sequential chemical adjustments to the waste stream which can remove substantially all toxic organics and heavy metals therefrom.

Abstract: Water or sewage which contains sludges containing organic waste materials or waste materials which can be chemically precipitated are mixed with a flocculant consisting of a metal salt solution and are subsequently degasified. Thereafter, the pure water and organic sludge containing admixed metal hydroxide are separated from each other. The pH value of the sludge mixture is decreased until the metal hydroxides are dissolved as metal salts so that the organic sludge can be separated from the resulting metal salt solution. The metal salt solution is recirculated for re-use as a flocculant. Because the separated sludge still contains metal salts, it is treated with wash water and may possibly be further acidified. After the separation, the pH value of the wash water is increased to precipitate a metal hydroxide sludge, which is separated from the wash water and recycled to the degasified sewage.

Abstract: Separation of clarified water and rapid settling of the particulate solids e.g. ash, slag, char and mixtures thereof from aqueous dispersions of quench cooling and/or scrubbing water as produced in the partial oxidation process for ash-containing solid carbonaceous fuels is effected by mixing with said dispersion a sulfonated product of humic acids and their salts and adjusting the pH of the mixture to a value in the range of about 2 to 6.

Abstract: A method is provided for the treatment of wastewater of pH ranging from about 1.5 to 3 containing at least about 100 ppm phosphorus as phosphate ions, at least about 50 ppm fluorine as fluoride ions and ammonia in excess of about 15 ppm NH.sub.3 (N)--T, the method comprising removing the phosphate and fluoride ions from the wastewater in a two-stage precipitation step; the first stage precipitation being conducted at a pH ranging from about 3.5 to 6.5 using an alkaline material selected from the group consisting of limestone (CaCO.sub.3) and lime [CaO or Ca(OH).sub.2 ] sufficient to form a precipitate which is removed to provide a filtrate of the wastewater which is treated in a second stage precipitation at a pH of at least about 10.5 using lime as the alkaline material sufficient to form a precipitate which is removed to provide substantially a clear effluent containing ammonia.

Abstract: Apparatus for generation of cavitation within a flowing liquid, wherein expenditure for equipment for purposeful generation of cavitation and control of the cavitated liquid portion can be achieved by passing the liquid from a high-level reservoir through a downwardly flowing path which includes an outlet nozzle, at least one pipe bend connected to the outlet nozzle and a drop-pipe with a control valve in the vicinity of the lower end of the drop-pipe.

Abstract: This invention involves a process and apparatus for removing dissolved and undissolved oil and chemical additives from waste and/or produced water streams. The process involves contacting a selected gas with the produced water stream, the selected gas utilizing hydrogen bonding and dipole interactions with the contaminants to remove them from the water. The rise rate of the selected gas is accelerated by mixing natural gas with the selected attractive gas. The selected gas and natural gas are recovered by the application of vacuum to the waste stream after treatment. The selected gas is separated from the natural gas by compressing and cooling the combined gas stream, venting the majority of the natural gas stream while the selected gas is liquified, then expanding the selected gas before returning it to the flotation vessel. Means are also provided for mixing the selected and natural gases with the contaminated water stream at line pressure so that mixing is intimate and flotation is accelerated.

Abstract: A method is provided for combining a high pH steam condensate with a flow of a acidic geothermal brine from which the steam is extracted so as to inhibit the formation of suspended particulate matter, such as heavy metal sulfides, calcium carbonate and iron hydroxide, by the chemical reacting of such impurities as hydrogen sulfide and ammonia in the condensate with such impurities as heavy metals, iron and calcium in the brine. The method includes acidifying the steam condensate, preferably by hydrochloric acid, to reduce the pH to between about 7 and about 4.5 and then combining the acidified condensate with the brine. In a silica crystallizer stage in which flashed brine is contacted with a silica seed material to cause silica removal from the brine, the treated condensate is combined with the brine in a low pressure crystallizer upstream of brine clarification and reinjection stages.

Abstract: A solid-liquid slurry, particularly sugar juice, is flocculated and clarified in an arrangement including a clarifier tank containing therein a mud bed of concentrated removed solids. A preflocculating vessel extends into the top of the clarifier tank and includes upper and lower chambers. The slurry is introduced into the upper chamber to flow turbulently therein, thereby deaerating the slurry. The slurry is transferred from the upper chamber to the lower chamber while the turbulent flow of the slurry is changed to a laminar flow. A flocculating agent, for example a suitable polymer, is introduced into the slurry, such that solids of the slurry coagulate as flocs in the lower chamber. The thus preflocculated slurry is introduced directly into the clarifier tank at a level beneath the surface of the mud bed therein. The liquid of the slurry percolates upwardly through the mud bed and is filtered, thus forming clarified liquid, and the flocs of solids settle downwardly into and form the mud bed.

Abstract: A process for the removal and recovery of mercury and, if desired, other heavy metals from incinerator waste water produced by washing waste gases from incinerators, which comprises adding to the waste water a reducing agent or a combination of oxidizing and reducing agents, subjecting the thus added waste water to stripping treatment in the presence of ferrous ion to obtain a mercury vapor-containing gas and simultaneously form spinel type crystalline compounds and then cooling said gas to separate and recover the mercury. If desired, said spinel type crystalline compounds are also removed from the mercury-free waste water.

Abstract: There is proposed a process for the purification of fluorinated lubricants, free from hydrogen, such as perfluorinated ethers or chlorofluorocarbons, whose elimination can be dangerous for the environment owing to the fluorine release, such a process consisting in dissolving the lubricant in a fluorochlorinated hydrocarbon, then in precipitating by means of a grease solvent, in separating, in degasing and finally in filtering in order to remove the mechanical impurities.

Abstract: This invention relates to recovery of fatty acids from sewage scum and the subsequent upgrading of the fatty acids as a processed oil through vacuum distillation and deodorization.

Abstract: Water intended for injection into an oil reservoir is freed from oxygen by gravitating the water through a vacuum tower. Gases liberated from the water by the vacuum process are drawn off at the bottom of the respective stages of the tower. Liberated nitrogen at the top of each stage will then flow down through the tower in cocurrent flow with the water and thus act as an internal stripping gas reducing the partial pressure of oxygen in the gaseous phase. Gases and vapors drawn off from the bottom of each vacuum stage after the first stage are pressurized to the pressure of the preceeding stage and reinjected into that stage.

Abstract: The problem of rising sludge in biological wastewater treatment secondary clarifiers is overcome by minimizing entrainment of nitrogen gas with mixed liquor entering the transfer pipe to the clarifier such that the level of dissolved nitrogen in the biomass settling in the clarifier remains less than that in equilibrium with nitrogen gas at the pressure prevailing in the biomass. This invention is most efficacious in cases where soluble oxides of nitrogen are present and are reduced by the biomass to elemental nitrogen. In accordance with one described embodiment the excess nitrogen is removed by degassing of the mixed liquor in the effluent pit of the system by deepening and widening the usual pit in such manner that the rate of descent of mixed liquor therein to a discharge outlet is less than 0.4 feet per second and the depth is greater than 4 feet, thus permitting the gas-containing macrobubbles to rise to the surface of the pit where these are degassed.

Abstract: Oil is dehydrated and/or desalted by the influence of a dewatering and desalting formulation which can be characterized as an admixture of (i) a demulsifier preferably an alkylene oxide alkyl phenol-formaldehyde condensate such as a poly ethoxylated nonylphenol-formaldehyde condensate and (ii) a deoiler which is usefully a polyol such as ethylene glycol or poly (ethylene glycol) of Mw ranging from 106 to 44,000 and preferably ethylene glycol.The aqueous formulation may usefully contain a cosolvent such as isopropanol.

Abstract: A method is provided for combining a high pH steam condensate with a flow of an acidic geothermal brine from which the steam is extracted so as to inhibit the formation of suspended particulate matter by the chemical combining of impurities in the condensate and brine. The method includes acidifying the steam condensate, preferably by hydrochloric acid, to reduce the pH to between about 7 and about 5.5 and then permitting the acidified condensate to outgas such volatiles as hydrogen sulfide and carbon dioxide before combining the condensate with the brine, formation of such insolubles as heavy metal sulfides and calcium carbonate being thereby inhibited. In a silica crystallizer stage in which flashed brine is contacted with a silica seed material to cause silica removal from the brine, the treated condensate is combined with the brine in a low pressure crystallizer upstream of brine clarification and reinjection stages.

Abstract: A system for treating water includes an aerator or degasifier that is fluidly connected to a blower that moves gases released from the water cascading down in the aerator over slat trays or plastic packing media. The released gases enter a gas scrubber and are treated with an iron salt solution that removes undesirable gases and that form a sludge that is removed from the scrubber. The residual gases, mostly nitrogen, argon, and other minor gases found in ambient air, flow into the aerator.In some instances, the gas scrubber also includes, in addition to the iron salt solution treating equipment, equipment for treating the released gases with caustic soda solution.

Abstract: The nickel content of a waste water stream, such as a stream of grey water that is separated in the decanting operation of a partial oxidation process or blow-down water from a gas quench cooling and/or scrubbing operation is reduced to below 1 mg/l to produce an environmentally upgraded water stream. In the process, the dilute waste water stream containing nickel impurities at a temperature in the range of about 60.degree. to 220.degree. F. is mixed with a water soluble material selected from the group consisting of formaldehyde, ionizable polysulfide salt, and hydrogen peroxide; and with dimethyl glyoxime. The pH is adjusted to a value in the range of over 7 to 11 by the addition of a base material and a water insoluble nickel precipitate forms. The precipitate and other insoluble matter are separated from the water by means of at least one conventional solids-liquid separator, and a stream of upgraded water is produced.

Abstract: There is disclosed a process for purification of waste waters accumulating from the production of pulp, particularly from chlorine bleaching of pulp, which comprises the combination of the following steps:(a) release of solid particles from the waste water in a series-connected, mechanical purification stage,(b) introduction of the pre-cleaned waste water into an electrolysis installation, wherein the waste water is subjected to constant movement during an anodic oxidation treatment, and an electric potential differential is plotted between the electrodes and the pH of the waste water is set and maintained at approximately 1 to 6.5 in a known manner,(c) transfer of the waste water thus treated from stage (b) into a flocculation (sedimentation) zone, in which an aqueous solution of a powerful cationic polyelectrolyte is fed to the waste water at room temperature and under constant movement, and the pH is set and maintained at 1 to 6.

Abstract: A method for the treatment of geothermal brines to control the precipitation of silica is disclosed. A sulfate-rich liquid is introduced into geothermal brine within a production well prior to flashing or is introduced into the residual geothermal brine remaining after the brine has been flashed to produce steam. The sulfate in the liquid reacts with the barium, calcium, and/or lead salts within the brine to produce a colloidal suspension which serves to accelerate precipitation of silica from the brine and to adsorb the precipitated silica particles. The colloidal suspension with its adsorbed silica particles is then removed from the brine by conventional gravimetric or filtration methods.The method of the invention substantially reduces the deposition of silica in wellbores and in energy extraction equipment and facilitates removal of the silica from the brine. The method further reduces the deposition of silica in injection wells wherein the silica cleansed brine is discharged.

Abstract: This invention relates to an improved process for treating a cyanic liquid containing copper(I) cyanide complex ion which comprises heating the liquid at a temperature of not lower than 200.degree. C. in the presence of a water-soluble metal hydroxide, whereby the decomposition of the CN group of copper(I) cyanide complex ion is accomplished in a high rate in a single batch producing a relatively small amount of sludge even when the liquid has a high CN concentration.

Abstract: A method for removing the excess sodium and byproducts of reaction which occur during the destruction of PCBs from oil. A predetermined quantity of water is mixed with the decontaminated oil and the byproducts, which include sodium chloride and polyphenyl polymer, to form sodium chloride and sodium hydroxide. Centrifuging removes most of the oil from the remaining aqueous mixture which then is agitated and treated with carbon dioxide gas to form less hazardous sodium carbonate and sodium bicarbonate. Any excess carbon dioxide gas is vented to the atmosphere and the sodium carbonate and sodium bicarbonate is collected into containers for disposal. Small amounts of oil remaining in the aqueous waste mixture that is discharged from the centrifuge is decanted from the remaining material in a waste separator due to its lighter specific gravity. A pump intermittently injects waste from the waste separator into a converter where it reacts with the carbon dioxide gas.

Abstract: Carbonates and bicarbonates are removed from the sludge of tar sands tailings ponds whereby solids settle from the sludge more rapidly than in the presence of the carbonates and/or bicarbonates. Hydrolyzed starch is used as a flocculant in the process and alcohol may also be used to assist in the settling and/or to improve the characteristics of the settled sludge for subsequent dewatering.

Abstract: Apparatus and a method of adding CO.sub.2 to softened water flowing through a series of interconnected flash chambers after the softened water has been directed out of a settler. The inlet of the settler receives preheated hard water after the hard water has passed through a series of interconnected preheating chambers, there being a preheating chamber for each flash chamber, respectively. Each preheating chamber and the corresponding flash chamber comprise a stage of a multi-stage water softening system, the preheating and flash chambers of each stage being separated by a partition defining an opening near the top portion of the stage to place the respective first and second chambers of each stage in fluid communication with each other and to allow flashed, heated water vapor from the flash chamber to pass into direct, admixing contact with cooler, hard water sprayed into the preheating chamber to preheat the hard water.

Abstract: Wastewater is continuously disinfected by combining the wastewater with sufficient acid to reduce the pH of the wastewater to less than about 4 and with sufficient SO.sub.2 that the wastewater has a selected free SO.sub.2 content of at least 5 mg/liter. The combined SO.sub.2 /wastewater is maintained at the selected free SO.sub.2 content for at least about 5 minutes. The wastewater can be treated by dissolving SO.sub.2 into a first portion of the wastewater and combining the first portion with SO.sub.2 dissolved therein with a second portion of the wastewater stream. SO.sub.2 can be stripped from the wastewater, and the stripped SO.sub.2 can be recycled.

Abstract: An integrated process for treatment of wastewater from steam boiler clean operations, containing sodium nitrite and also usually heavy metal ions such as Cu, Fe, Pb, Cr, Cd, Zn and Ni, as well as suspended solids and sludge, to remove the nitrite, substantially reduce the amount of such metal ions and remove suspended solids and sludge in the treated wastewater. The process comprises adding sulfamic acid to the wastewater, particularly in about stoichiometric proportions with respect to sodium nitrite to form gaseous nitrogen. The reaction takes place at ambient temperature and atmospheric pressure. An alkali such as sodium hydroxide is added to the resulting solution in amount sufficient to raise the pH thereof to about 10, and precipitating the metal ions.